The Psychopathology and Affective Science (PAS) program in the Department of Psychology at Stanford University provides training for careers ranging from basic research in affective processes and neuroscience to applied research in psychopathology. It emphasizes the experimental study of psychological and psychobiological mechanisms, theory development, and applications to problems of mental health and disorder. The psychology department at Stanford has a long history of training researchers with expertise in basic psychological processes studied within the context of real-world problems. We believe that the best research focuses on core psychological and psychobiological mechanisms, and that progress is most rapid when mechanisms are understood in the context of improving mental health. Trainees are predoctoral students working towards a Ph.D., and postdoctoral fellows seeking advanced training in psychopathology and affective science. Funds are requested to support four predoctoral and two postdoctoral trainees per year. The training curriculum includes a solid foundation in core courses and advanced seminars dealing with basic and applied psychological mechanisms, supplemented by specialized seminars that examine new theoretical and methodological advances. Emphasis is placed on research methods and the integration of divergent theories and methods to address and elucidate critical problems. Trainees begin their intensive training in research by means of a tutorial system in which each trainee collaborates closely with a particular faculty member. As they proceed through the program, graduate student trainees take increasing responsibility for originating and conducting research studies, and plan an individualized program of elective courses to acquire skills and background relevant to their specific research interests. Postdoctoral fellows have access to the full array of training opportunities throughout Stanford, and work closely with designated faculty mentors to establish a tailored research and training program.